Sliding door



J. SCHAEFER March 6, 1934.

SLlDING DOOR Filed Feb. 20, 1932 A S11/manto@ J'Hco CHHEFER,

ttomta y 7 Il) ll Patented Mar. 6, 1934 UNITED STATES PATENT GFFICE 6Claims.

My invention relates to sliding doors; especially to sliding doors suchas are used in refrigerator display cabinets. More particularly, myinvention relates to means for sealing such sliding doors when they aremoved to closed position.

Usually, a refrigerator display cabinet or show case is provided in itsback wall, often an inclined back wall, with a rectangular door frame;and within this rectangular door frame are mounted two sliding doorsslidable in spaced parallel planes between a closed position in whichthe trailing end members oi` the doors overlap and open positions wherethe doors overlie each other or nearly overlie each other, and to whichthe opened door slides past the other door. If such doors are made toslide freely, they will not completely seal the door opening when theyare closed, but will permit some leakage around their edges and betweentheir overlapping trailing edges. 1f the doors are made to fit tightlyenough to seal the opening, they will not slide easily. It is the objectof my invention to provide means in association with such doors to sealthem when they reach closed position and at the same time to permit themto slide freely.

In order that the doors may slide easily, 1 desirably mount them onrails fixed to the door frame longitudinally thereof and projecting intogrooves in the top and bottom edges oi the door, and 1 provide at thebottom of the ,groove in the lower edge of the door a set of rollers forcooperating with the rail associated with that groove. For sealing thedoors when they reach closed position, provide means extending along thetop and bottom frame members and projecting between the two doorsproviding faces slightly out of parallel with the planes in which therespective doors slide and closest to each of such planes at the endframe member toward which the respective doors slide when moved toclosed position; and 1 alter the edges of the adjacent faces of the twodoors to present surfaces parallel with those provided by the sealingmeans and in position to wedge against those faces -when the doors areclosed. On the end frame members I provide similar sealing meanspresenting faces similarly oblique to the planes in which the doorsslide, and 1 similarly alter surfaces at the ends of the doors tocooperate therewith. On the adjacent faces of the trailing end door-endmembers I mount co-operating sealing strips which engage each other toseal the gap between such trailing edges when the doors are closed.

The accompanying drawing illustrates my invention: Fig. 1 is a irontelevation of a door frame and a pair of doors equipped with sealingmeans embodying my invention; Fig. 2 is a section taken on the line 2-2of Fig. 1; Fig. 3 6C' is a section similar to that of Fig. 2 but withoutshowing the doors; Fig. 4 is a vertical section taken on the line 4-4 ofFig. 1, showing the doors in end elevation and illustrating in dottedlines how a door may be removed from a door frame; Fig. 5 is anisometric view of one of the doors; and Fig. 6 is an end elevation ofthe display cabinet, partly shown in section to reveal the relativeposition of the door frame with respect to such display cabinet. 7C

A display cabinet or show case such as that shown in Fig. 6 usually hasin its back wall a door casing 10 containing a pair of sliding doors.This door casing comprises a top member 11, a bottom member 12 and twoend members 13. For mounting a pair of doors 14 and 15 within the doorcasing, the casing is provided with two pairs ci rails, the two rails ofeach pair being co-planar. The respective top rails 16 of each pair aremounted longitudinally on the lower surface of the top frame member 11,and the respective bottom rails 17 of each pair are mounted on the uppersurface oi the bottom member 12. Each door has an upper groove 18 forco-operating with the upper rail 16, and similarly has a lower groove 19for co-operating with the bottom rail 17. The lower groove 19 is of lessdepth than the upper groove 18 and is provided at its bottom with a pairof rollers 20. Each door is of slightly less height than the opening in`which both are situated, and its upper groove 18 is sufficiently deep topermit the door to be raised :far enough to disengage the lower groove19 from the bottom rail 17 so that the door may be removed from the doorframe. An intermediate position through which a door being removedpasses is shown in dotted lines in Fig. 4 of the drawing.

The two parallel pairs of rails are spaced apart to permit each of thetwo doors mounted respectively on the two pairs of rails to slide freelyalong its pair of rails past the other. By reason of the rail and groovemounting for the doors, and the rollers associated with the lowergrooves 19, each door is easily slidable.

For sealing the doors when they reach closed position, a ridge 22extends from the lower surface of the top frame member 11 downward tobetween the two doors 14 and 15, and a similar ridge 23 extends upwardfrom the bottom frame member 12 to between their bottom edges. These tworidges, desirably made of metal, may be substantially co-planar, buttheir plane is slightly out of parallel with the planes of the two pairsof rails in the direction of door movement, and they are closest to therails for each door at the end of the frame toward which that doorcloses. Where the ridges 22 and 23 overlie the faces of the doors, thosefaces are altered, as by rabbeting, to provide surfaces on the doorsparallel with the ridges and in position to approach closely the sidefaces of those ridges when the doors are closed. Desirably, the surfacesprovided by these rabbets are covered with strips of some compressiblesealing material such as rubber or felt. With this a1'- rangement, whena door is closed, the surfaces provided by the rabbets and covered withthe sealing strips will wedge themselves against the sides of the ridges22 and 23, and will thus seal the top and bottom edges of the door.

For sealing the leading edges of the doors, the end frame members 13 arealso provided with ridges 24, co-planar with the ridges 22 and 23; andthe leading edge of each of the doors is rabbeted to present a surfacewhich will approach closely the side surface of the ridge 24 when thedoor is closed. These surfaces may also be covered with strips ofsealing material.

When both doors are in closed position, and trailing edges overlap, andfor sealing the gap between such overlapping edges, each may be providedwith a sealing strip 25 in position to engage the similar sealing stripon the other door when the doors are in such closed position.

It will be obvious that the rollers 20 in the bottom of the groove ofeach door will roll on the lower rail 17 and permit the doors to moveeasily. By reason of the centrally positioned ridges and the cooperatingsurfaces provided on the adjacent faces of the two doors by the rabbets,and the fact that the sides of such ridges and the cooperating surfaceson the doors are similarly out of parallel with the planes in which thedoors move, those door surfaces will engage the sides of the ridges on1ywhen the doors approach closed position, and will be out of engagementto permit the doors to move freely when they are in any other positionthan the nearly closed one. By reason of this arrangement, the doorswill be freely slidable through substantially all their movement, andyet will readily seal the door opening when they are closed.

I claim as my invention:

1. In a door structure having a pair of sliding doors each beingopenable by sliding toward a position in which one overlies the other, asealing ridge projecting from the door frame to between the adjacentfaces of the respective doors at their edges, said sealing ridge beingslightly out of parallel with the planes of movement of the the edges ofsaid door faces presenting surfaces parallel with the sides of saidsealing ridge, the ridge and such surfaces on each door being arrangedto engage when such door is closed.

2. In a door structure having a pair of sliding doors each beingopenable by sliding toward a position in which one overlies the other, asealing ridge projecting from the door frame to between the adjacentfaces of the respective doors at their edges, said sealing ridge beingslightly out of par'- allel with the planes of movement of the doors,

and rabbets at the edges of said door faces presenting surfaces parallelwith the sides of said sealing ridge, the ridge and such surfaces oneach door being arranged to approach each other closely when such dooris closed, there being sealing strips of compressible material on suchsurfaces.

3. In a door structure having a pair of sliding doors each beingopenable by sliding toward a position in which one overlies the other, asealing ridge projecting from the door frame to between the adjacentfaces of the respective doors at their edges, said sealing ridge beingslightly out of parallel with the planes of movement of the doors,rabbets at the edges of said door faces presenting surfaces parallelwith the sides of said sealing ridge, the ridge and such surfaces oneach door being arranged to effect a seal therealong when such door isclosed, and means associated with the trailing edges of the respectivedoors for cooperating to form a seal therebetween when the doors areclosed.

4. In a door structure having a pair of sliding doors each beingopenable by sliding toward a position in which one overlies the other,sealing ridges extending respectively from the top and 1 bottomdoor-frame members betweenthe respeclar sealing ridge extending fromeach end member in position to overlap the leading edge of 1 a doorface, said ridges being out of parallel with the planes of door movementin the direction of such movement, the portions of the door face whichwill be overlapped by such ridges being altered to present surfacesrespectively parallel 1 with said ridges, said ridges and surfaces beingarranged to approach each other to effect seals therealong When thedoors are moved to closed position.

5. In a door structure having a pair of sliding 1 doors each beingoperable by sliding toward a position in which one overlies the other,sealing ridges extending respectively from the top and bottom door-framemembersv between the respective planes of movement of the doors inposition 1 to overlap the side edges of the door faces, a similarsealing ridge extending from each end member in position to overlaprespectively the leading edge of a door face, said ridges being out ofparallel with the planes of door movement in the 1 direction of suchmovement the portions of the door face which will be overlapped by suchridges being altered to present surfaces respectively parallel with saidridges, said ridges and surfaces being arranged to approach each otherto effect 1 seals therealong when the doors are moved to closedposition, and means on the trailing edges of the respective doors`adapted to engage when the doors are closed to form a sealtherebetween.

6. A door structure, comprising a door frame, 1 guiding-means on each oftwo sides of said door frame, a door slidable along said guiding-means,a portion of the face of the door along each of its sliding edges beingaltered to present a planar surface slightly out of parallel with theplane 1 of door movement in the direction of such movement, and means on.said door frame presenting surfaces parallel with said altered surfacesand arranged to be approached thereby to effect a seal therealong. 1

JACOB SCHAEFER.

